1. Field of the Invention
This invention relates to a process for synthesis of a mixed metal oxide catalyst containing oxides of molybdenum, bismuth, iron, cesium and, optionally, other metals for the production of unsaturated aldehydes from olefins, such as methacrolein by gas phase catalytic oxidation of isobutylene in the presence of air or another gas containing molecular oxygen.
2. Description of the Prior Art
Many catalysts have been disclosed for use in the production of acrolein or methacrolein by catalytic vapor phase oxidation of propylene or isobutylene. U.S. Pat. No. 4,170,570 discloses a catalyst for production of unsaturated carboxylic acids and anhydrides containing molybdenum; at least one of tin, copper germanium, antimony, bismuth, tellurium, manganese, arsenic, alkali metals, iron, magnesium, zinc and/or nickel; at least one of tungsten or chromium; and at least one of vanadium, phosphorus, antimony or cobalt. The catalyst was prepared by dissolving oxides of the metal components in distilled water and refluxing the mixtures until a dry catalyst was obtained.
U.S. Pat. No. 4,511,671 discloses a catalyst for manufacturing methacrolein containing molybdenum, tungsten, bismuth, iron; at least one of nickel and/or cobalt; at least one of alkali metals, alkaline earth metals and/or thallium; at least one of phosphorus, tellurium, antimony, tin, cerium, lead, niobium, manganese and/or zinc; and silicon, aluminum, zirconium, and/or titanium. Nitric acid was used to dissolve metal nitrates.
U.S. Pat. No. 4,816,603 discloses a catalyst for production of methacrolein and methacrylic acid containing molybdenum, tungsten, bismuth, iron, nickel, antimony, at least one of potassium, rubidium, and/or cesium, at least one of phosphorus, boron, sulfur, silicon, selenium and/or germanium, at least one of zinc and/or lead and at least one of magnesium, cobalt, manganese and/or tin. Nitric acid was used to dissolve metal nitrates.
U.S. Pat. No. 4,916,103 discloses a catalyst for oxidation of propylene to acrolein and acrylic acid containing molybdenum, bismuth, iron, cobalt or nickel, phosphorus; at least one of arsenic, antimony, tin, thallium, tungsten, an alkaline earth metal, zinc and/or chromium; and at least one of sodium, potassium, rubidium, cesium and/or indium. Nitric acid was used to dissolve metal nitrates.
U.S. Pat. No. 5,138,100 discloses a catalyst for preparing methacrolein with composition (1) of the formula:
 MoaBibFecXdYeZfOg
where X is at least one of Ni and Co, Y is at least one of K, Rb, Cs and Tl, Z is at least one of the elements belonging to Groups 2, 3, 4, 5, 6, 7, 11, 12, 13, 14, 15 and 16, specifically beryllium, magnesium, calcium, strontium, barium, titanium, zirconium, cerium, niobium, chromium, tungsten, manganese, copper, silver, zinc, cadmium, boron, aluminum, germanium, tin, lead, phosphorus, arsenic, antimony, sulfur, selenium and tellurium, a is 12, b is 0.1 to 10, c is 0 to 20, d is 0 to 20, e is 0 to 2, f is 0 to 4, and g satisfies the valence requirement and composition (2) of the formula:LnhMoaOjwhere Ln is at least one of the rare earth elements, h is 0.2 to 1.5, i is 1 and j satisfies the valence requirement. Nitric acid was used to dissolve metal nitrates.
U.S. Pat. No. 5,144,090 discloses a catalyst for preparing acrolein or methacrolein containing molybdenum, bismuth, iron; at least one of nickel and/or cobalt; and at least one of potassium, rubidium, cesium, titanium, zirconium, niobium, chromium, tungsten, manganese, copper, silver, zinc, cadmium, boron, aluminum, silicon, germanium, tin, lead, phosphorus, arsenic, antimony, silicon, selenium and/or tellurium. Nitric acid was used to dissolve bismuth nitrate.
U.S. Pat. No. 5,166,119 discloses a catalyst for producing methacrolein and methacrylic acid containing molybdenum, tungsten, bismuth, iron, antimony; at least one of nickel and/or cobalt; at least one of cesium and/or thallium; at least one of magnesium, manganese, zinc, barium and/or chromium; and at least one of phosphorus, boron, sulfur, silicon, cerium, potassium and/or rubidium. Nitric acid was used to dissolve metal nitrates and it was disclosed that the amount of nitric acid outside a certain range lowered the activity of the catalyst.
U.S. Pat. No. 5,245,083 discloses a catalyst for preparing methacrolein containing a first composition of molybdenum, bismuth, iron; at least one of nickel and/or cobalt; at least one of tungsten, beryllium, magnesium, sulfur, calcium, strontium, barium, tellurium, selenium, cerium, germanium, manganese, zinc, chromium, silver, antimony, lead, arsenic, boron, phosphorus, niobium, copper, tin, aluminum, zirconium and/or titanium mixed with a second composition of molybdenum and at least one of potassium, rubidium and cesium. Nitric acid was used to dissolve bismuth nitrate.
U.S. Pat. No. 5,276,178 discloses a catalyst for producing methacrolein and methacrylic acid containing molybdenum, tungsten, bismuth, iron; at least one of nickel and/or cobalt; at least one of alkali metal and/or thallium; at least one of alkaline earth metals; at least one of phosphorus, tellurium, antimony, tin, cerium, lead, niobium, manganese, arsenic and/or zinc; and at least one of silicon, aluminum, titanium and/or zirconium. Nitric acid was used to dissolve bismuth nitrate.
U.S. Pat. No. 5,532,199 discloses a catalyst for producing acrolein and acrylic acid or methacrolein and methacrylic acid containing molybdenum, bismuth, iron; at least one of nickel and/or cobalt; at least one of magnesium, zinc, manganese, tin and/or lead; at least one of phosphorus, boron, sulfur, tellurium, silicon, selenium, germanium, cerium, niobium, aluminum, titanium, zirconium, tungsten and/or antimony; and at least one of potassium, sodium, rubidium, cesium and/or thallium. Nitric acid was used to dissolve metal nitrates.
U.S. Pat. No. 5,602,280 discloses a catalyst for producing acrolein and acrylic acid or methacrolein and methacrylic acid containing molybdenum, bismuth, iron; at least one of nickel and/or cobalt; at least one of manganese, zinc calcium, magnesium, tin and/or lead; at least one of phosphorus, boron, arsenic, tellurium, tungsten, antimony and/or silicon; and at least one of potassium, rubidium, cesium and/or thallium. Nitric acid was used to dissolve bismuth nitrate.
U.S. Pat. No. 5,856,259 discloses a catalyst for producing methacrolein and methacrylic acid containing molybdenum, bismuth, iron; at least one of nickel and/or cobalt; at least one of magnesium, zinc, manganese, tin and/or lead; at least one of phosphorus, boron, sulfur, tellurium, silicon, germanium, cerium niobium, titanium, zirconium, tungsten and antimony; and at least one of potassium, sodium, rubidium, cesium and/or thallium. Nitric acid was used to dissolve metal nitrates.
U.S. Pat. No. 6,028,220 discloses a catalyst for producing acrolein and acrylic acid containing molybdenum, bismuth, nickel, cobalt, iron; at least one of tin, zinc, tungsten, chromium, manganese, magnesium, antimony and/or titanium; and at least one of potassium, rubidium, thallium and/or cesium. Nitric acid was used to dissolve bismuth nitrate.
Prior art discloses the use of nitric acid to dissolve metal nitrates, particularly bismuth nitrate, in the synthesis of catalysts for producing acrolein and acrylic acid or methacrolein and methacrylic acid. Use of nitric acids generates nitrate salts which can decompose violently during heating (calcination). Also, oxides of nitrogen are produced during calcination which is undesirable from an environmental standpoint.
U.S. Pat. No. 6,461,996 discloses acetic acid as a product of a process for selective oxidation of propane to acrylic acid, acrolein and acetic acid using a catalyst containing molybdenum, vanadium, gallium, palladium, niobium and at least one of lanthanum, tellurium, germanium, zinc, silicon, indium and/or tungsten.
U.S. Pat. No. 6,043,184 discloses a heteropoly acid for direct catalytic oxidation of alkanes to unsaturated carboxylic acids, specifically propane to acrylic acid. Acetic acid/water was used as a medium to mix sodium acetate, iron nitrate and nickel nitrate to prepare a trimetal acetate which was a reactant in the process to prepare the heteropoly acid. Acetic acid was also a reaction product of the oxidation of propane.
U.S. Pat. No. 4,918,214 discloses acetic acid and water as a solvent for the alumina support of a vanadium-phosphorus-tungsten catalyst for the ammoxidation of propane.
U.S. Pat. No. 4,107,204 discloses a three-step process for the oxidation of propylene to acrylic acid in the presence of a palladium catalyst and acetic acid.
U.S. Pat. No. 4,849,539 discloses dissolving indium metal in acetic acid and isobutyl alcohol in the preparation of a vanadium-phosphorus oxide catalyst precursor for the production of maleic anhydride from n-butane, oxygen and nitrogen.